About 3D layers (Mesh, Gaussian Splatting, BIM)

TerraExplorer supports several types of 3D layers, including 3D mesh layers, 3D Gaussian Splatting (3DGS) layers, and BIM-based layers:

§  3D Mesh Layers – High-resolution, continuous 3D models built from connected textured polygons. These models are stored on the server in 3DML or o3DML formats for optimized visualization and efficient streaming.

§  3D Gaussian Splatting (3DGS) Layers – 3D model layers generated directly from photos using volumetric Gaussian primitives rather than explicit polygonal meshes or surfaces, enabling highly realistic visualization without mesh reconstruction or texture baking. 3DGS layers are stored on the server in o3DML format.

·        BIM Layers – 3D model layers with Building Information Modeling (BIM) content, including geographic location and attribute data. BIM layers are stored on the server in 3DML format.

Loading and Importing 3D Layers

Mesh and Gaussian Splatting layers in 3DML or o3DML formats can be loaded directly into TerraExplorer. Most other 3D layer formats are converted to Skyline’s proprietary, stream-optimized 3DML format, upon import:

§  Models (Point feature layers that reference individual models) – Converted to 3DML in TerraExplorer using the Models to 3DML tool.

§  DAE (LODTreeExport.xml) – Converted to 3DML upon import to TerraExplorer using the Import and Convert tools.

§  OSGB – Converted to 3DML upon import to TerraExplorer using the Import and Convert tools.

§  3D Tiles (tileset.json) – Converted to 3DML upon import to TerraExplorer using the Import and Convert tools.

§  Building Information Modeling (BIM) – Converted to 3DML upon import to TerraExplorer using the Import BIM tool.

Working with 3D Layers in TerraExplorer

When a 3D layer is loaded into TerraExplorer, the 3D Layer contextual tab is displayed, from which you can perform 3D layer operations. Most of the 3D layer operations are available only for 3D layers in 3DML or o3DML formats:

§  Set Display Style – Select a 3D model display style, e.g., texture, wireframe, or x-ray.

§  Classify – Create a feature layer with classification polygons containing attribute data relevant to the mesh layer. Classification enables you to visually distinguish different areas of the 3D layer and perform spatial and attribute queries on the feature layer that is classifying the 3D layer. The classification is dynamic, reflecting any changes to the polygon features, and requires no pre-processing.

§  Modify – Modify the elevation values in a designated area of a 3D layer using a modify mesh layer object (only supported for mesh layers).

§  Mark for Retouch – Edit 3D layer imperfections, such as bumps, irregular surfaces, or floating artifacts.

§  Scale and Rotate – Correct inaccuracies in 3D layers’ scale, rotation and positioning.

§  Export to Models – Export polygonal areas of a 3D layer, e.g., buildings, to individual OBJ models (only supported for mesh layers).

§  Export to Mesh – Export 3D layer to 3D Tiles (tileset.json) or I3S/SLPK formats. TerraExplorer supports 3D Tiles 1.1.

Some operations are only available for mesh layers with associated feature layers (i.e., mesh created from point feature layers with individually referenced 3D model files, imported BIM layers, or mesh layers classified using the legacy Classify Mesh Layer tools):

§  Spatial Queries - Select features based on their spatial relationship with a polygon, line or point that you draw, or with an existing object.

§  Search by Attribute - Search the layer attribute database files to easily edit the attribute values of multiple features and to create a new shapefile based on the filtered data. 

§  Display by Attribute - Display only selected areas of the mesh model that match a specific attribute value.

§  Colorize by Attribute - Colorize the mesh model based on attribute value, with a different color assigned to each attribute value.

See "Working with 3DML’s Feature Layers" in this chapter for more information.